OP-ED COLUMNIST; What's Worse Than An Oil Spill?

By MARK BITTMAN

Published: April 20, 2011

A year ago, the Deepwater Horizon drilling rig exploded, gushing nearly five million barrels of oil into the Gulf of Mexico before it was finally capped three months later. It was by most accounts a disaster. But when it comes to wrecking our oceans, the accidental BP spill was small compared with the damage we do with intent and ignorance.

I recently talked about this with two men who specialize in ocean affairs: Carl Safina, the author of ''A Sea In Flames'' and the president of the Blue Ocean Institute; and Ted Danson, (yes, that Ted Danson), who recently published Oceana (the book) and is a board member of Oceana, the conservation organization he helped found. As Safina said, ''Many people believe the whole catastrophe is the oil we spill, but that gets diluted and eventually disarmed over time. In fact, the oil we don't spill, the oil we collect, refine and use, produces CO2 and other gases that don't get diluted.''

That CO2, of course, leads to global warming and climate change, as well as what's called ocean acidification, which might be thought of as oceanic global warming and is a greater catastrophe than any spill to date. The oceans absorb about 30 percent of the carbon dioxide in the atmosphere, creating carbonic acid. Since the start of the industrial revolution we've added about 500 billion metric tons of carbon dioxide to the oceans, which are 30 percent more acidic than they were a couple of hundred years ago.

This acidification makes it difficult for calcifying organisms - coral, snails and oysters and other mollusks, and more - to build shells and skeletons sturdy enough for them to survive. Many of these are on the bottom of the food chain and, as they begin to die off (we've already seen massive oyster declines on the Pacific coast), the effects trickle up. Acidification has already wreaked havoc on coral reefs, on which about 25 percent of all marine life depends. By the end of this century, Safina says, the ocean will begin dissolving coral reefs - unless we make a big change in our fossil-fuel use.

If acidification endangers marine life leisurely, fishing does it quickly. Around 70 percent of global fish stocks are fully or overfished, and 30 percent have collapsed, which means they produce less than 10 percent of their original capacity. Commercial fish catch has declined by 500,000 tons per year since 1988, not for lack of effort, money or technology - in fact because of those factors - but for lack of fish. The danger becomes dual, says Danson: ''If you're overfishing at the top of the food chain, and acidifying the ocean at the bottom, you're creating a squeeze that could conceivably collapse the whole system.''

There's some hope in the overfishing department, and strangely enough the gulf is an example of this. When huge areas were closed to fishing during the spill, many fish stocks rebounded. (As Safina, who is clearly no fan of oil spills, says, ''If you ask the fish whether they'd rather have an oil spill or a season of fishing, I wouldn't be surprised if they'd vote for another blowout.'') We've seen this before: fish stocks boomed during World War II, when the North Atlantic was not a safe place to be. This is why marine reserves - areas where no fishing is allowed - make so much sense.

The U.S. is strong on combating overfishing, in fisheries management, establishing quota or even moritoria on certain species, and in adjusting those subsidies that encourage industrial fishing, that which uses the most damaging methods like bottom trawling and is responsible for horrific amounts of bycatch, the unintentional capture of nontarget fish that is usually left for dead. Ninety percent of the world's fishers - those who fish at subsistence level and just above - catch only 10 percent of the world's fish; industrial and often subsidized ships bring in 90 percent. The World Trade Organization has been slowly moving toward stronger regulation of subsidies for industrial fishing, but very slowly.

The reality is that a tremendous amount needs to change for our oceans and fish stocks to recover. Scary as it has been, the fishing fix seems at least imaginable, if we create more marine sanctuaries, crack down on overfishing and continue to pressure retailers to employ sustainable seafood policies. This last is especially encouraging: Greenpeace's annual report, ''Carting Away the Oceans,'' announced last week that 15 of 20 major U.S. food retailers had passing grades in their fish-selling policies. (This year Safeway took the top spot and is poised to achieve Greenpeace's first ''good'' rating.) When the first report was made, in 2008, none of the stores received positive scores; that's progress.

Yet ocean acidification looms, and for this there is only one solution: reducing carbon emissions. You do that by using less fossil fuel, by conservation or substitution or both. On this front, the U.S. is behind the curve, and we stand to lose a lot more than coral.

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This is a more complete version of the story than the one that appeared in print.